254 



4. Crinoid segments aaa 



.".. Dalmanella testudinaria (Dalman) aaa 



6. Hemiphragma tenuimurale Ulrieh a 



7. [soteluE gigas de Kay e 



8. Mitoclema? mundulum Ulrieh r-<- 



'.). Nematopora ovalis Ulrieh r-c 



10. Paehydietya acuta (Hall) e 



1 1 . Paehydietya fimbriata Ulrieh r 



12. Platystrophia trentonensis n. sp e 



13. Plectambonites sericeus (Sowerby) r-c 



14. Prasopora simulatrix orientalis Ulrieh a 



15. Rafinesquina alternata (Emmons) r 



16. Rhinidictya exigua Ulrieh r 



17. Rhinidictya paupera Ulrieh ' r-c 



.",. Mill Dam Falls. 



The IS Jill Dam Falls or Fourth Falls is formed of thin bedded, rather 

 coarse-grained and fossiliferous limestone. The following species 

 identified: 



1. Chasmotopora reticulata (Hall) e 



2. Crinoid segments a 



3. Dalmanella testudinaria (Dalman) a 



4. Plectambonites sericeus (Sowerby) a 



5. Rhinidictya paupera Ulrieh r-c 



0. Power Do m Interval. 



The Power Dam Interval includes almost all of the division of the Prosser 

 and Cummings report except the upper few feet, which were collected from 

 separately. The base of this interval is marked by a heavy stratum of lime- 

 stone. Above this lies thin-bedded compact lime-stone, part of the strata 

 .^omewhat crystalline, separated by shaly layers. At the upper end of the 

 gorge the layers show the greatest amount of folding visible anywhere in the 

 Trenton Falls section. The strata are very fossiliferous and the following 

 species were collected: 



1. Calymene senaria Conrad a 



2. Ceramoporella distincta Ulrieh c 



3. Chasmotopora reticulata (Hall) aaa 



